Weird horizontal band on Xiaomi Ultrawide Monitor 34 after sleep

[megasoft1978]

I'm not sure I'm able to explain it correctly but when the monitor goes to sleep and I try to wake it up, there are some horizontal bands moving.
It takes almost a minute to come back normal.
Is it possible some issues with the refresh rate?

[waydabber]

Well, i don't know. :) You might want to post a video about it.

If you are all right with it, I'll move this over to discussion, maybe other Xiaomi users can chime in!

[megasoft1978]

@waydabber Is this enough?
https://user-images.githubusercontent.com/72806043/182399995-e0b29494-9f93-4592-8689-a4637feaf5e8.mp4

[megasoft1978]

• I'm not using dummy mirroring as I'm using native smooth scaling
• I haven't tried as I disabled the monitor to go to sleep mode.

I'll let you know if that suggestion solves the problem.
Eventually disabling the sleep mode solves the issue.

Thank you :)

[waydabber]

Hmm. If you are using smooth scaling and the issue is happening only after sleep, then it might be a DDC related issue as BetterDisplay might restore the last DDC brightness upon startup. I saw you are using HDMI which on Mac has issues relaying DDC commands and sometimes causes issues with displays. Try disabling Enable advanced display control and let me know if that changes things. If it does then you can re-enable Enable advanced display control and try disabling DDC specifically for the display or try using USB-C/DisplayPort to connect the display to the Mac.

[megasoft1978]

@waydabber I just tried with Enable advanced display control disabled and I'm getting the same issue.

[waydabber]

Well, I have no idea then what is wrong. :( If you are not using a dummy and advanced control is disabled then BetterDisplay should basically do nothing special upon wake except for reloading some configurations. However if you only use native smooth scaling, the changes should be semi-permanent so you don't actually need to run BetterDisplay continually to have your preferred resolution available.

Can you try quitting BetterDisplay for a while and keep using stuff with sleep enabled and see if the issue 100% does not occur while BD is not running - just to make sure? If you already tried this, then you don't have to repeat it, I'll then try to think about what else could be done to nail down the issue.

[megasoft78]

This is happening even without Better Display so it's an issue between my monitor and Mac OS.
I'll investigate it.
Thank you. :)